DESCRIPTION: The Epidemiology Core is proposed for the collection of risk factor and cancer incidence data; and for assistance with mammogram, medical records, pathology materials, and biological specimens. These data are essential to the completion of all four Projects. The Minnesota Breast Cancer Family Study currently includes 426 families and over 11,000 members. Additional data collection must be obtained on all living female relatives and marry-ins over the age of 18 years through two mail surveys (Project 4). This includes collection of new risk factor data and the occurrence of cancer since our last contact with them. Newly included family members for project 1 must be interviewed via telephone to collect risk factor and cancer occurrence information. New breast and ovarian cancer diagnoses and all cancer diagnoses in the newly included family members of the selected Project 1 families must be validated through medical records, pathology materials, or death certificates. Recent mammogram are needed for all women 40 years and over, especially if they attained the age of 40 years since our last contact and are members of the 57 families identified for Project 3. Finally, since mammography is a good screening tool for breast cancer, recent mammogram can help identify incident cases, critical to Projects 1, 2, and 4. Projects 1, 2 and 3 are all dependent upon DNA samples for completion of study aims. The Epidemiology Core will coordinate the collection of blood samples needed on study subjects. Because each of the four projects will utilize some or all of the same sets of families, it is critical that data collection activities proceed in a coordinated manner. The role of the Epidemiology Core is to collect all data and samples needed for each of the four proposed projects in an efficient and timely manner. With the increased complexity brought about by multiple projects and overlap of individual participants among projects, this Core serves an essential function.